INVESTIGATION WITH CHITOSAN-OXALATE OXIDASE-CATALASE CONJUGATE FOR DEGRADING OXALATE FROM HYPEROXALURIC RAT CHYME

Enteric hyperoxaluria manifests due to hyperabsorption of dietary oxal ate, secondary to a variety of chronic gastrointestinal disorders. The potential use of chitosan immobilized oxalate oxidase-catalase conjug ate to deplete the oxalate content of food materials, while they are i n the digestive tract has been evaluated by treating rat stomach chyme with such an enzyme preparation. Oxalate oxidase, obtained from beet stem, was adsorbed on chitosan along with catalase and then cross link ed with glutaraldehyde to stabilize the derivative. This chemical modi fication of oxalate oxidase brought about a shift in its optimal pH fr om 4.2 to 3.8 with a marginal increase in its K-m. Compared to native enzyme, the modified oxalate oxidase exhibited increased storage stabi lity, higher thermal stability and enhanced resistance to proteolytic digestion and heavy metal inactivation. These improved properties of t he immobilized oxalate oxidase Possibly render it suitable for oral ad ministration under hyperoxaluric conditions.